Immune-driven inflammatory events are a significant cause of many chronic inflammatory diseases where prolonged inflammation causes tissue destruction and results in extensive damage and eventual failure of the effected organ. The cause of these diseases is unknown, so they are often called autoimmune, as they appear to originate from an individual's immune system turning on itself. Conditions include those involving multiple organs, such as systemic lupus erythematosus (SLE) and scleroderma. Other types of autoimmune disease can involve specific tissues or organs such as the musculoskeletal tissue (rheumatoid arthritis, ankylosing spondylitis), gastro-intestinal tract (Crohn's disease and ulcerative colitis), the central nervous system (Alzheimer's, multiple sclerosis, motor neurone disease, Parkinson's disease and chronic fatigue syndrome), pancreatic beta cells (insulin-dependent diabetes mellitus), the adrenal gland (Addison's disease), the kidney (Goodpasture's syndrome, IgA nephropathy, interstitial nephritis), exocrine glands (Sjogren's syndrome and autoimmune pancreatitis) and skin (psoriasis and atopic dermatitis).
In addition, there are chronic inflammatory diseases whose aetiology is more or less known but whose inflammation is also chronic and unremitting. These also exhibit massive tissue/organ destruction and include conditions such as osteoarthritis, periodontal disease, diabetic nephropathy, chronic obstructive pulmonary disease, artherosclerosis, graft versus host disease, chronic pelvic inflammatory disease, endometriosis, chronic hepatitis and tuberculosis. In these diseases, the tissue destruction often damages organ function, resulting in progressive reductions in quality of life and organ failure. These conditions are a major cause of illness in the developing world and are poorly treated by current therapies.
Inflammation of skin structures (dermatitis) is a common set of conditions which include actinic keratosis, acne rosacea, acne vulgaris, allergic contact dermatitis, angioedema, atopic dermatitis, bullous pemiphigoid, cutaneous drug reactions, erythema multiforme, lupus erythrametosus, photodermatitis, psoriasis, psoriatic arthritis, scleroderma and urticaria. These diseases are treated using a wide array of therapies, many of which have very severe side-effects.
Current disease-modifying treatments (if any) for immune-driven conditions include neutralising antibodies, cytotoxics, corticosteroids, immunosuppressants, antihistamines and antimuscarinics. These treatments are often associated with inconvenient routes of administration and severe side-effects, leading to compliance issues. Moreover, certain drug classes are only effective for certain types of inflammatory diseases, e.g. antihistamines for rhinitis.
Bupropion is a marketed anti-depressant with serotonin and noradrenaline reuptake inhibition as its central mechanism of action. Metabolites of bupropion are described in the literature as having therapeutic utility in various diseases of the central nervous system.